An exemplary tape library device used in, for example, a computer system contains a plurality of substantially box-shaped magnetic tape cartridges and accesses these magnetic tape cartridges in response to instructions from a high-order device, such as a computer.
Such a tape library device is usually equipped with a cassette magazine with a plurality of tape cartridge slots. The magnetic tape library device includes a conveyance mechanism for moving the magnetic tape cartridges out of the cassette magazine to a reader/writer which is fixed to a predetermined position.
The magnetic tape cartridges contained in the magnetic tape library device can be replaced by an administrator user and thus the cartridges received in each of the cassette slots are not always identical.
The magnetic tape library device therefore usually uses magnetic tapes each of which has an identification barcode printed thereon. The barcode is read by a barcode reader provided in a medium conveyance mechanism to thereby identify the magnetic tape cartridge received in each of the slots of the cassette magazine.
Since the conveyance mechanism of such a magnetic tape library device usually inserts the magnetic tape cartridge which is being conveyed through a cassette opening provided in the reader/writer, a recording surface of the magnetic tape cartridge often faces the cassette opening. In addition, the magnetic tape cartridge is inserted in the reader/writer and ejected from the slot often along the same axial direction.
For these reasons, the conveyance mechanism often ejects and inserts the magnetic tape cartridges at the surfaces opposite to the recording surfaces, and the magnetic tape cartridges are often received in the slots of the cassette magazine with the surfaces opposite to the recording surfaces facing the conveyance mechanism.
In addition, as described above, the related art magnetic tape cartridges have been identified by a barcode reader provided in the conveyance mechanism.
Thus, the related art magnetic tape cartridges often have an identification barcode printed on the surface opposite to the reading surface.
Recently, in addition to the above-described magnetic tape library devices having a conveyance mechanism and a reader/writer which are separately provided (hereinafter, referred to as a “separated magnetic tape library device”), magnetic tape library devices in which a reader/writer is incorporated in a conveyance mechanism (hereinafter, referred to as an “integrated magnetic tape library device”) have been proposed (see, for example, Japanese Laid-open Patent Publication Nos. 2001-126354 and No. 11-53813).